[clang-tools-extra] [clangd] Include the operator name in documentHighlight (PR #220518)

[Christian Kandeler via cfe-commits]

ckandeler wrote:

> clangd crashes on the following example
> 
> ```c++
> #define PLUS +
> struct S { void operator PLU^S(int); };
> ```
Fixed.


https://github.com/llvm/llvm-project/pull/220518